1. Field of the Invention
The present invention relates to an operating device for influencing image information displayed on a display surface with a movable operating element and with means for the quantitative determination of adjustment (displacement) motions of the operating element.
2. Description of the Prior Art
In image processing, particularly medical image processing, image information items, such as tomograms or 3D visualizations of three-dimensional anatomic objects, which are acquired with the aid of diagnostic devices and visualization computers, are displayed at display surfaces for diagnosis, therapy or operation planning. In order to influence the manner by which the image information items are displayed, one or more input means, such as a keyboard, a joystick, a trackball or mouse, are normally connected to the visualization computer. By manipulating the mouse and/or other equivalent input means, a marker that is faded into displayed image information can be moved relative to the image information (known as xe2x80x9czoomxe2x80x9d), a selection of a number of displayed image information items, or a scrolling through different views of image information items can be undertaken.
For example, PCT Application WO 97/15840 describes a medical imaging system with an input device, which is fashioned such that the sequence parameters can be modified by set-up means during a sequence. The set-up means can include a joystick, a mouse or a track ball, for example.
German OS 198 19 218 describes an operating element that is preferably fashioned as a handheld operating element and that essentially exhibits the functionality of a joystick.
U.S. Pat. No. 5,506,605 discloses a three-dimensional mouse, which can be freely moved in space.
Furthermore, European Application 0 429 391 describes an input device for a computer, which also exhibits the functionality of a three-dimensional mouse.
U.S. Pat. No. 5,303,148 describes a voice-operated medical and imaging system. The input ensues, for example, by means of a microphone, whereby the system commands activate procedures that are preprogrammed and stored in a computer.
German OS 195 01 581 discloses a foot-operable input device for medical-technical system workstations, particularly for surgery.
German OS 197 40 382 describes a movable electronic component, which is provided with keys, which can be operated from outside and by means of which the function of the component can be controlled. This component can be particularly fashioned as a waterproof computer mouse.
It has proven disadvantageous that the known input means normally are two-dimensionally adjustable input means that are bound to a specific operating location, so that it is often difficult to transfer image information items, particularly three-dimensionally visualized image information items, from one view into another view in a simple way with the aid of such input means.
A three-dimensionally displayed object is rotated by means of a mouse, for example, such that the marker, which is shown at the display surface and which is coupled to the mouse, is positioned onto a point of the object, which is shown at the display surface and which is to be rotated, by corresponding motions of the mouse. Given a simultaneous actuation of a key of the mouse, the mouse is perpendicularly moved to the rotational axis around which the object is to be rotated, effecting the rotation of the object. This type of utilization of the mouse for rotating a three-dimensionally visualized object is referred to as a xe2x80x9cvirtual trackballxe2x80x9d. It is not easy for the user to get accustomed to the operation of the virtual trackball. Moreover, the user can easily loose his or her orientation regarding the current orientation of the object after a few rotation actions with respect to complex three-dimensionally displayed objects.
An object of the present invention is to provide an operating device of the aforementioned type wherein the handling of the operating device proceeds intuitively for the user.
This object is inventively achieved in an operating device for influencing medical image information items, which are displayed at a display surface, with a movable operating element and with means for quantitatively determining adjustment motions of the operating element, wherein the display of the medical image information items displayed at the display surface can be influenced solely by motions of the operating element alone. The inventive operating device therefore is fashioned such that the means for determining adjustment motions, which preferably include a calculating unit by means of which adjustment motions are quantitatively determined, acquires motions of the operating element and converts these into control signals for influencing the display of the image information items, so that the display of medical information items displayed at the display surface can be modified without further activities of a user handling the operating element, i.e., without simultaneously operating an operating element, solely by motions of the operating element in a specific direction and around a specific adjustment scope. For example, the display can be scrolled between different views of an object displayed at the display surface simply by moving the operating element or a corresponding rotation of an object displayed at the display surface can be effected by rotating the operating element. Since a motion of the operating element thus effects an influence on the display of a medical image information corresponding to the motion, an intuitive and therefore facilitated handling of the operating device results for the user.
In a particularly preferred embodiment of the invention the operating element can be freely moved in six degrees of freedom. As a result of the free movability of the operating element, there are no restrictions regarding the handling of the operating element. The free movability of the operating element has proven to be particularly advantageous for influencing the display of three-dimensionally visualized objects, since each motion of the operating element is followed by a corresponding motion of the three-dimensionally visualized object. Therefore, the user can understand every motion of the object, since an immediate relation between the motion of the operating element and the motion of the object on the display surface is always present.
In a version of the invention the operating element of the operating device has a number of operating actuators which respectively allow the operation of the operating device in different operating modes.
In a version of the invention, the operating element thereby has at least four operating actuators. The actuation of a first operating actuator places the operating device in a selection mode, in which a marker, which is mixed into a displayed image information, is moved relative to the image information, and a selection can be made by actuating the operating actuator again. The actuation of a second operating actuator places the operating device in a second operating mode, in which the size of an item of image information, which is displayed at a display surface, can be influenced solely by moving the operating element. A third operating mode of the operating device can be activated by a third operating actuator, whereby corresponding motions of the medical image information displayed at the display surface are effected by motions of the operating element. The actuation of a fourth operating actuator places the operating device in a fourth operating mode, in which scrolling between different views of image information items, which can be displayed at the display surface, is enabled by moving the operating element.
In another embodiment of the invention, the operating element of the operating device has a microphone, so that the display of the medical image information can be influenced by voice control in addition to the influencing of the medical image information as a result of motions of the operating element.
In a further embodiment of the invention the operating device has an actuator with which the functional occupation of the aforementioned operating actuators of the operating element can be set (selected). The functional occupation of the operating actuators therefore is customized in an application specific fashion.
In an embodiments of the invention, electrical signals, which can be wirelessly transmitted via a transmission device at the operating element to a reception device of the operating device that is connected to a processor for processing the signals, are generated by operating an operating actuator and/or by speaking into a microphone. A facilitated handling of the operating element thus results, since a cable extending between the movable operating element and the signal processor, which is stationary relative to the operating element, is not present. Such a cable can cause stumbling or tripping.
In another embodiment of the invention the means for quantitatively determining the adjustment motion of the operating element determine the coordinates of the operating element in a reference coordinate system and transform these into coordinates of an image coordinate system that can be written into the medical image information. The means for quantitatively determining the adjustment motion can subject the coordinates that are determined with regard to the reference coordinate system and/or the coordinates that are determined with regard to the image coordinate system to a mean value filtering. Undesired, unsteady motions of the operating element by the operating person can be advantageously smoothed by the mean value filtering, so that sudden changes with respect to the display of the medical image information items at the display surface do not occur as a result of small unsteady motions.
In a further embodiment of the invention the means for the quantitative determination of the adjustment motion of the operating element can be adjusted such that the scope or limits of the adjustment motion, which is necessary in order to influence the display of a medical image information, can be prescribed. Therefore, the sensitivity of the operating device, namely the range of an adjustment motion of the operating element, regarding which the operating device responds for initiating an action, can also be adjusted in an application-specific fashion.
In further embodiments of the invention, the operating element is fashioned as a handheld operating element and is capsuled in a liquid-tight manner, so that the operating element can be utilized in environments in which contact of the operating element with fluids, such as body fluids, may occur. Due to the liquid-tight encapsulation of the operating element, the operating element is washable and easy to clean. Furthermore, the liquid-tight encapsulation makes it possible to sterilize the operating element in a simple way, so that it can be used in antiseptic environments such as operating rooms.